1. Technical Field
Example embodiments of the present invention relate to a technology of positioning, and more specifically to an apparatus for measuring position of other apparatuses, which can be used to measure relative positions between a plurality of apparatuses located in an arbitrary environment, and a method for the same.
2. Related Art
Generally, robot has been developed for industrial purpose, used for factory automation, or used for performing tasks on behalf of human in extreme environments in which human cannot perform tasks. Robotic engineering has been used for space development industry of high technology, and advanced persistently so that developments of human-friendly domestic robots become possible. Also, robot is being used, instead of medical devices, for treatment of biological tissues of human by introducing robot into human body which could not be treated by traditional medical devices.
According to the remarkable advances, the robotic engineering is becoming newly coming high technology substituting information revolution due to internet technology and biological engineering which has become popular as following the internet technology. For example, cleaning robots are representative examples which enlarge a scope of robotic engineering from industrial domain focusing on heavy industry to domestic domain focusing on light industry.
On the other hand, as necessities for mapmaking and target objective searching in extreme environment which human cannot access increase, a mobile robot has been used for performing such the tasks.
Especially, in the case that a map is made for a large area or a target objective is searched in a large area, used is a method that a plurality of robots is introduced and each robot of the plurality of robots is responsible of making a map corresponding to each divided region of the large area or searching the target objective in each divided region of the large area.
As described above, when a plurality of robots is introduced in a certain environment and each robot performs tasks in divided region corresponding to it, each robot should identify positional information of other robots in order to increase efficiency of the tasks.
That is, in order to prevent redundant task of robots, reduce time required for performing task, and integrate results of tasks performed by robots efficiently, it is preferable that each robot can identify positions of other robots, and perform its task in region which is not redundant with regions of the other robots.
As current methods for measuring pose of robot, a landmark is installed in a ceiling of space in which robots are located. Then, infrared transceivers equipped in the robots transmit infrared signals to the landmark and receive infrared signal reflected from the landmark. By using the infrared signal reflected from the landmark, poses and positions of the robots can be measured. However, in the above-described method, installing the landmark in the ceiling is a cumbersome task, and each robot should know positions of the landmark installed in advance. Therefore, the method cannot be used for general purposes.
Alternatively, being used is a method of installing a laser sensor in robot, and making each robot to use the laser sensor for scanning surrounding environments, acquiring two-dimensional map of the surrounding environments, and identifying its position based on the acquired two-dimensional map. However, although the method can enable each robot to identify position of itself, the method has shortcomings that each robot cannot identify its position accurately because a large amount of error may be generated when the surrounding environments have non-uniform surfaces.
Also, although the above mentioned two methods are being used currently, in the case that a plurality of robots is located in a specific space, there is a problem that each robot cannot determine positions of other robots in real time.